OverviewI investigate how speech categories are processed in the brain. My research is informed by both neuroscience and linguistics, and many of my research questions are devoted to classic questions on phonetics and speech perception: How do we categorize continuous speech into discrete linguistic units? How do we perceive speech sounds? How do we learn new speech categories? I am interested in learning about the perceptual and neural mechanisms involved in these processes, and much of my current work is dedicated to enhance language learning and speech processing. In my experiments, I collect neural and behavioral responses in a variety of learning, perceptual and speech production tasks. I also use machine learning to decode speech categories from neural signals and identify neural markers of speech processing and speech learning.

My work at the SoundBrain Lab is linked -but not limited- to two federal grants funded by the NIH and DARPA. The first one (NIH) explores the interaction between cortical and subcortical networks in speech processing. Here, I designed a brain-computer interface that we are currently using to train people to improve neural responses to non-native speech sounds in real-time. Our goal here is to assess the extent to which people is able to modulate early auditory neural plasticity. We are also interested in evaluating the contributions of egocentric neural modulation to speech processing and learning. The second grant is circumscribed to the Targeted Neuroplasticity Training program (DARPA). Here, we are using auricular transcutaneus vagus nerve stimulation to accelerate non-native speech training. In rodent models, pairing vagal nerve stimulation (VNS) with sounds enhances cortical auditory plasticity that is specific to stimulus spectrotemporal properties. VNS-induced cortical plasticity is similar to cortical plasticity induced by nucleus basalis stimulation, suggesting that the effects arise from upregulation of the cholinergic system. Our goal here is to examine the extent to which pairing auricular transcutaneous vagus nerve stimulation with speech training facilitates learning of non-native speech in humans.

Llanos, F., & Gutierrez, C. (2012). ”Mispeleens” in the early Romance scripta. Presented at The 12th Annual Graduate Symposium sponsored by the Department of Foreign Languages and Literatures of Purdue University, West lafayette, Indiana. March 3-4.